Do you have a DMM yet? If not, I'd budget part of that towards a nice Fluke or other good brand. You'll need one.
Metcal makes nice irons, but I'm partial to the Hakko 936. Excellent build quality, lots of available tips and spot-on reliability. Check around to see if you can find a used one to save a few dollars. Same with the DMM.
Other than that, get a Radio Shack solder bulb for desoldering, and get one of the packs of probes, etc. that are soldering tools. I have a set of old dentist picks that are supremely useful, as well. I got them in a small hardware store, but ask your dentist what he does with his old picks. Maybe he'll give you some.
Get some copper alligator clips to use as heatsinks. Also, you'll want a pair of flush-cut wirecutters, a wirestripper, a pair of needlenose pliers, and a set of small screwdrivers, including Torx (hex) head drivers.
If you have any budget left over, look into getting an isolation transformer and a Variac.
You can always find used tools at a Hamfest, as well. Go look at the events calendars here:
http://www.arrl.org
If there's one in your area, go. You'll get good deals on tools and should have some boxes of tubes to dig through, as well.